This port is opened by ICM subsystem during its initialization, as part of engine start up.
Any changes to this port would require a restart of ICM sub system ( or Engine restart) for it to start listening on this new port.

The issue here may be that IVR can not connect to the VRU PIM on the Peripheral Gateway. Please check if the VRU connection port on IVR and PG are both configured to the same port. The default VRU connection port is 5000 which is opened for PG connection. IVR can also use a different port provided the same is configured on the PG as well.

Recommended Action

Change the VRU port to use the same port as that of PG and restart IPIVR Engine. Verify that ICM subsystem is in ACTIVE state in IPIVR.